UPDATE: Former Donald Trump campaign manager Paul Manafort and his longtime business associate Rick Gates were indicted by a federal grand jury on 12 charges, including conspiracy against the U.S., Special Counsel Robert Mueller's office announced Monday.

Other charges against Manafort and Gates include money laundering, being an unregistered foreign agent and seven counts of failure to file reports of foreign bank and financial accounts.

The indictment was unsealed Monday after Manafort and Gates were told to surrender to law enforcement.

It says, "In total, more than $75 million flowed through offshore accounts" and it refers to Manafort's "hidden overseas wealth to enjoy a lavish lifestyle in the United States."

The indictment says that both men generated tens of millions of dollars as a result of their lobbying work for the Ukraine. They hid the payments, from 2006 through 2016, by laundering the money through scores of U.S. and foreign corporations, partnerships and banks, according to the charges.

Manafort laundered more than $18 million, which the indictment says he concealed from the federal government.

From 2008 to 2014, Manafort wired $12 million to be sent to vendors for personal items, including $5.4 million on home improvements in the Hamptons, $934,350 to an antique rug store in Virginia, $520,440 to a clothing store in Beverley Hills and $655,500 for landscaping in New York, according to the indictment.

He also spent millions more on homes: $1.5 million on Soho condo; $3 million on a Brooklyn brownstone and $1.9 million on a Virginia house.

The two men are the first people to be charged in the investigation by Mueller into the Trump campaign's alleged ties to Russia and Moscow's interference in the election last year.

Four sources told NBC News that there was a statute of limitations issue in play that may have helped drive Monday's charges by Mueller.

The sources said the indictment does not preclude other charges being filed against Manafort in the future.

The news was first reported by The New York Times.

A White House source said officials there are "not surprised" to see movement from the special counsel, adding: "The White House has been saying for weeks the special counsel is moving far more quickly and deliberatively than people have been reporting. The fact that the special counsel is actively performing its duties does not come as a surprise to the White House."

House Minority leader Nancy Pelosi, D-Calif., said, "Even with an accelerating Special Counsel investigation inside the Justice Department, and investigations inside the Republican Congress, we still need an outside, fully independent investigation to expose Russia's meddling in our election and the involvement of Trump officials. Defending the integrity of our democracy demands that Congress look forward to counter Russian aggression and prevent future meddling with our elections."

NBC News confirmed on Friday that a federal grand jury in Washington had approved the first criminal charges in the special counsel's probe, marking a significant milestone in an inquiry that's roiled Trump’s presidency.

Manafort, who served on the Trump campaign from April to August 2016, has long been under investigation in connection with his lobbying work for a Russian-backed Ukrainian political party that also involved his former partner, Gates.

Legal experts have long predicted that Manafort would be charged and speculation ramped up after the FBI conducted an early-morning search in July at his Alexandria Virginia apartment using a "no-knock warrant."

Gates is a lesser known figure, who worked with Manafort in Ukraine and flew to Moscow for meetings with associates of Oleg Deripaska, a Russian oligarch who paid Manafort and Gates tens of millions of dollars, NBC News has reported.